DE2602605A1 - METHOD OF MANUFACTURING A PANEL CONSTRUCTION AND DEVICE FOR USE IN THIS PROCESS - Google Patents

Description

Paienian lawyers

Bipl-Ing. Woiigang fioichel

6 Frankfurt a. M. 1
Parksirasso 13

8378

KAWASAKI JUKOGYO KABUSHIKI KAISHA, Kobe-Shi, Japan

Method of making a panel structure and apparatus for use in this method

The invention relates to a method of manufacturing a panel structure from a skeletal one Framework and a skin panel attached to the framework. The invention is also concerned with a Apparatus for stretching and optionally heating a sheet for use in the method. The panel construction is particularly suitable for vehicles, ships, structures and the like.

The invention is generally concerned with panel structures made of building materials, such as those in sheet metal and Thin panel constructions for the roof and side cladding of many vehicles, ships, buildings and other structures can be used. The invention is concerned in particular with a method for producing Panel constructions of the type described above, wherein the skin panel or the skin sheet in such a way to be attached to the framework so that no welding deformations in the sheet metal or in the panel appear.

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There is a great need to reduce the weight of various structures, in particular of railroad cars. To meet this need, you have the wall thickness of the panel or Fairing constructions of the vehicles reduced. For steel, the wall thicknesses of skin plates are or Skin sheets on the order of 1.2 to 1.6 mm. The framework components have a thickness of the order of 2.3 to 4.5 mm. As a result of the tendency, the strength of the To reduce components, there is a risk that when thin plate structures of the type described above Assembly deformations occur, for example in the roof and side wall panel structures.

Of the various types of deformations that occur, about 50% can be attributed to warping or bending of the skin sheets, which are distortions. About h0% of the deformations are based on an irregular sag. These two types of deformations make up 90 ^ 6 of the total deformations. The distortion deformations of the skin plates or skin sheets also include local stresses caused by rolling and stresses due to welding. Therefore, when a thin plate or a skin sheet of the type described is attached to a lattice-shaped framework, for example by welding, various kinds of deformations in the form of concave and convex bulges occur in the individual rectangular fields of the skin sheet.

It is common to remove these convex and concave deformations by a deformation removal process Eliminate, in which after the production of the panel structure each field is locally heated, for example by point or line heating, and then quickly

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is cooled. The ones for this deformation removal procedure Working time taken accounts for about 20 to 25 Sa of the assembling time of a vehicle body. the Removal of the deformations is therefore associated with a great deal of work and high costs.

Furthermore, the deformations cannot be removed from stainless steel sheets, otherwise the discolour thin metal sheets and the panel will lose its commercial value. Stainless steel sheets are therefore only used as corrugated skin sheets. Corrugated skin sheets are very expensive and have a smaller size aesthetic value. In the case of skin sheets made of aluminum materials, the effectiveness of deformation removal is very low due to point heating, as aluminum has a very high thermal conductivity. In some cases it is therefore impossible to remove the deformations. When processing skin sheets made of aluminum therefore extremely complicated operations, such as the use of auxiliary cooling plates to make the aluminum panels.

In summary, it can be stated that, according to the prior art, the occurrence of weld deformations cannot be avoided in thin-plate or skin-plate constructions and that it is necessary remove the resulting deformations in a suitable reworking process.

The invention is based on the object of the thin-walled or panel constructions in such a way to ensure that there are no deformations before, during and after the application of the skin panels to the framework occur in the skin panels.

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This is basically achieved according to the invention in that a skin panel has a panel construction processed in such a way before and during attachment to a skeletal framework that there is a residual tensile stress in the skin panel of the finished panel construction. These Residual tensile stress is caused by the Skin table is subjected to such a physical condition that it assumes a state in which it is elastically stretched in its geometric surface with respect to the normal state, and that in this stretched State the skin panel is attached to the framework.

A method of making a panel construction of the type described is in accordance with the invention thereby characterized in that prior to the attachment of the skin panel to the framework, only the skin panel is one appropriate tensile stress that is below the elastic yield point in the tensile stress state held skin panel is attached to the framework and that then the tensile forces of the Skin plate to be taken away.

A method of making a panel structure of the type described is characterized according to the invention in that the skin plate prior to attachment on the framework is brought to a suitable temperature so that it is in a thermally expanded State is that the skin plate in this thermally expanded state at room temperature Is attached to the framework and that the heat supply to the skin panel is then adjusted to to allow cooling to room temperature.

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A method of making a panel structure of the type described is in accordance with the invention thereby characterized in that the above-described stretching process and the above-described heating process can be applied at the same time in order to achieve an overlay effect in the skin panel by stretching and heating. A further development of any one of the three methods described above is characterized according to the invention characterized in that prior to performing any of the aforementioned manufacturing steps, the skin panel is overstretched to subject them to a tensile stress that is above the elastic limit of elongation of the skin panel. if it is necessary, you can pre-stretch the skin sheet with a tension that exceeds the elongation limit, before performing the other steps to make the panel construction.

The invention is explained in detail with reference to a drawing. It shows:

Fig. 1 is a view of a skin sheet for the roof of a railroad car,

FIG. 2 is a view of a panel construction made using the skin panel shown in FIG has been made

3 is a view of a device for use in the method according to the invention,

FIG. 4 is a side view of the one shown in FIG Contraption,

5 is an enlarged side view of an essential part of the device shown in FIGS. 3 and 4;

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6 shows a graphic representation with an exemplary distribution of the residual tensile stress in a Skin panel in longitudinal direction,

7 shows a partial view of a panel construction for a side wall of a vehicle body,

Fig. 8 is a side view illustrating the manner in which a panel construction is implemented by the heating process according to the invention is produced,

Fig. 9 is a sectional view of the panel structure shown in Fig. 8 and of the essentials Parts of a device for producing the panel construction and

Fig. 10 is a graph showing the temperature distribution in a "skin panel" when the panel is heated immediately prior to attachment to a framework.

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The following embodiment of the invention "relates to its use in making an enclosure structure for the roof of a rail vehicle or railroad car. An outer skin or a skin sheet 1 with the shape shown in Fig. 1 is produced in that a large number of rectangular, thin plate or sheet metal members 1a having a prescribed property by welding them together laterally get connected. The skin sheet 1 is provided at both ends with clamping portions 2, which be cut off later. In Fig. 2, a roof lining construction 4 is shown, which is produced thereby is that the skin sheet 1 is welded to a framework. The framework 3 is made up of end sheets 5, edge rails 6 and cross braces 7 joined together in the form of a grid.

The following describes the manner in which the roof lining structure 4 according to the invention is produced by using a stretching process:

1. The skin sheet 1 is in a state in which it is forced by means of a stretching device Is exposed to tensile stress or tensile elongation, attached to the framework 3, for example by welding.

2. After completion of production step 1. the forced tensile stress is removed. So is the production of the roof cladding construction finished.

An embodiment of a stretching device 8 for Applying tension to the skin panel 1 during manufacture of the roof cladding structure 4 is shown in FIGS 3, 4 and 5 shown. The device 8 contains a movable, active part 8a for generating the tensile stress

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and a stationary, reactive part 8b. The parts 8a and 8b have clamping heads 10a and 10b with opposing clamping chucks 9a and 9b which form the end sections of the skin sheet 1. At that. The clamping head has the opposite end of the chuck 9a 10a has a central Aufsattelungs- or articulation point, which via a pin joint 13a with the outer end a piston rod 11a of a hydraulic cylinder 11 is connected. The cylinder 11 is fastened at its head end to an anchorage 15a with a bolt and can be actuated by a hydraulic pressure system 12 connected via a hose 16. A central coupling point or articulation point of the clamping head 10b is on the opposite side of the chuck 9b via a hinge pin 13b with the one end of a rod 8b ,. connected to her other End is attached by a bolt to an anchorage 15b. The two anchors 15a and 15b are provided at a distance from each other. The articulated or bolted connections mentioned, in particular the pin joints 13a and 13b are provided in such a way that that the tensile force is applied to the skin plate 1 uniformly. In Figs. 3 and 4 shown heating devices 14 are not used in the stretching process described first

The effectiveness and usefulness of the invention in preventing the occurrence of deformations due to of welding in the manufacture of cladding or wall cladding is related to the roof cladding construction 4 explained.

As a result of the application of the forced Tensile or elongation force in the first manufacturing step the skin sheet 1 experiences an elastic longitudinal deformation. This is subject to the second manufacturing step

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Skin sheet 1 of elastic contraction deformation due to the removal of the forced tensile stress. These Deformation of the skin sheet 1 is forced by the framework 3, with a residual tensile stress in the Skin plate 1 remains.

The distribution of this residual tensile stress in the longitudinal direction of the skin plate 1 is shown in FIG. As a result of the application of the forced tensile force, after this load has been removed, a residual tensile stress distribution with a trapezoidal profile occurs in the skin plate, as is shown by a line P in FIG. 6. In a distribution area A, which is assigned to the central section of the sheet 1, no deformations occur. This distribution area A corresponds to a section of the line P, where the residual tensile stress is higher than a critical stress σ_, below which deformations occur. The level of the critical stress σ is slightly below the stress 0, so that the stress CP is actually a compressive stress. Even in the case of compressive stress, deformation of the skin sheet does not occur if the compressive stress is equal to the critical stress σ or is above this critical stress. In the practice of the invention, however, the skin sheet is treated so that only the residual tensile stress remains therein. In the distribution areas B, ie the end sections of the skin sheet 1, which correspond to those sections of the line P where the residual tensile stress is lower than the critical stress O ", deformations can occur, since the full forced stress is not applied in these areas.

Deformations, for example weld deformations, can thus be achieved according to the method according to the invention and local deformations existing in the skin sheet

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mations, by creating a uniform residual tensile stress in the entire sheet metal skin. Step into the hull construction made in this way therefore almost no deformations. The usual operations to remove such deformations can therefore be omitted.

In a further embodiment of the invention, in the manufacture of the outer shell structure the side wall of a railroad car as shown in FIG. 7, a heating process applied. In the finished state, such a cladding or shell construction 21 essentially contains a lattice-shaped framework 23 and a through Side skin sheet 22 attached to this framework 23 by welding. The skin sheet or skin sheet 22 is made produced in that numerous rectangular, thin plate or sheet metal elements by welding laterally be connected to each other. The skin plate 22 has openings 22a and 22b for doors and windows. The frame member 23 is produced in that a large number of angle frame elements 23a to one Lattice to be joined together. In the finished shell construction 21, the skin sheet 22 is latticed from the Framework 23 divided into several rectangular fields 24.

Next, with reference to FIGS. 8 and 9, the sequence of steps carried out according to the invention for Manufacture of the shell construction of the vehicle or wagon side wall explained:

1) On the surface of a table or a Plate 25, a thermal insulating material 26, for example asbestos in plate form, is placed.

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2) A skin plate or sheet 22 is placed on the insulating material 26.

3) A heating device 27, which can be, for example, a heated steel plate that has previously been ^{preheated to a temperature of the order of 150 0} G, is placed approximately in the middle of a field 24 on the skin plate 22 and with the help a press 28 pressed down against the skin plate 22 in order to heat ^{the plate 22 to a temperature of about 100 to 150 0 C.} These treatment conditions can be varied depending on the nature of the shell construction, the material of the skin sheet and the manner of welding.

4) When the skin sheet 22 is in a thermally expanded state due to heating, a framework 23 kept at room temperature is first provisionally attached and then welded.

5) Immediately after the welding, the heating device 27 is removed. Cool the welded parts to room temperature. This completes the manufacture of the shell structure.

The manufacturing process of the present invention described above is extremely effective in preventing deformation avoid. The skin sheet (viewed in a field 24) is subjected to thermal expansion. Here comes there is a temperature increase distribution as shown in FIG. This temperature increase distribution relies on the action of the preheated heater 27. The framework 23 becomes thermal during this attached to the skin plate 22 in the expanded state. Only then is the heating device 27 removed so that the

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2602805

Sheet 22 can cool. The thermal contraction and Deformation of the sheet 22, which would otherwise cause the cooling process are included in Framework 23. As a result, tensile stress remains in the skin panel 22.

This residual tensile stress prevents changes in shape, which would otherwise occur as a result of welding. In the field 24 there are therefore concave and convex deformations avoided. It is therefore not necessary to deformation after the shell construction has been completed to eliminate. By pressing the heating device against the sheet metal 22 by the press 28 during heating concave and convex deformations of the sheet metal during the heating process are also avoided.

For the production of a shell construction, a method is thus created according to the invention in which initially a skin plate or sheet is preheated to cause the skin sheet to undergo thermal expansion, and in which, in the thermally expanded state of the sheet, a framework is attached to the sheet. The thermal contraction that occurs while the sheet is cooling causes residual tensile stress in the sheet that avoids deformations in the sheet metal. Therefore occur in the wall or shell construction produced almost no concave or convex deformations. A previously common operation for removing such deformations can therefore be omitted. This also increases the risk of deterioration in the quality of the product and the risk of damage to the product is avoided. The manufacturing process according to the invention leads to savings in trained personnel and to a reduction in energy consumption. The manufacturing time is also greatly reduced. According to the invention The manufactured product is thus characterized by low manufacturing costs.

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The manufacturing process making use of preheating is particularly suitable for making cladding or wall constructions for side walls with openings in the skin sheets, as such
Skin plates or sheets of skin cannot be stretched or stretched. This applies generally to the manufacture of
Shell constructions in which one is perfectly
cannot achieve uniform distribution of the tensile stress when stretching. The described method according to the invention is particularly effective for preventing sheet metal deformations in cladding constructions made of aluminum material, from which deformations cannot easily be removed by point-wise heating in view of the high thermal conductivity of this material. Another advantage of this method is that it can also be, since the heating temperature is generally less than 150 ⁰ C is used for stainless steel materials, without any discoloration of the skin sheets or the thin boards occurs.

Another method according to the invention makes use of both the stretching process and the heating process to produce a siding structure, for example a thin panel structure for the roof of a railroad car. A skin sheet 1
and a framework 3 is used as is already on hand
1 and 2 has been described. The one in the
The roof cladding structure 4 shown in Figure 2 is then fabricated using a stretching and heating process as follows:

. 1) The skin sheet 1 is attached to the framework 3 in
attached to a state in which with the hand of the
3 to 5 described stretching device 8, a forced tensile stress is exerted on the skin sheet 1
and at the same time such areas of the skin sheet 1 on

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which the forced tensile stress cannot be exerted sufficiently, for example on the end sections, caused, under the action of the aforementioned heating devices 14, a thermal expansion .to do.

2) After completion of manufacturing step 1) the above-mentioned forced tension is removed and the heaters 14 are turned off. As a result, the skin plate 1 leads to the cooling. sliding thermal contraction. After completion The production of the cladding construction is finished after cooling down.

With regard to the structure and the mode of operation of an embodiment of the stretching device 8, reference is made to the explanation relating to FIGS. 3, 4 and 5. In addition to this representation, the heating devices 14, for example hot plates, are brought into close contact with the surface of the skin sheet 1 gripped by the clamping chucks 9a and 9b of the stretching device 8, specifically at locations close to the end sections of the sheet. These end portions of the sheet are heated in this manner, namely, for example, to a temperature of the order of 100 ⁰ C.

The effectiveness and utility of the invention in preventing the occurrence of deformation in manufacture of thin-walled or panel constructions will be explained with reference to the roof cladding construction 4.

The first step described above eliminates the deformations that occur during Welding during the production of the skin sheet 1

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stand, and also those caused by rolling local stresses. Furthermore, the skin sheet 1 experiences the application of the forced tensile force during the first manufacturing step involves an elastic length deformation. At the same time, the end sections lead of the skin sheet 1 to which the tensile force cannot be sufficiently communicated, a thermal one Expansion due to preheating. In the second production step, the skin sheet 1 then has an elastic one Contraction deformation as a result of the removal of the forced tensile force and a thermal contraction deformation resulting from the cooling after shutdown and accompanied the removal of the heating devices 14. The framework 3 acts on these deformations of the skin sheet 1 against, so that a residual tensile stress in the skin plate remains.

The distribution of this residual tensile stress in the longitudinal direction of the skin sheet 1 is shown in FIG. 6. The applied traction calls for its removal in the Skin sheet shows a residual tensile stress distribution which shows a trapezoidal curve and which is shown in FIG. 6 line P is shown. In a distribution section A corresponding to the central section of the sheet 1 no deformations occur, since there the residual tensile stress corresponding to line P is higher than a critical one Stress <J _ is possible below deformations are. On the other hand, in the stress distribution areas B at the end portions of the sheet 1, deformations can occur occur because there the residual tensile stress is below the critical Stress σ _ lies. This is due to the fact that in these areas B the forced tensile stress has not fully come into effect. In addition, however, in the areas B, that is to say in the end sections of the sheet metal 1, one represented by the line Q in FIG

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Contraction deformation stress (residual tensile stress) caused during the cooling time of the preheated sheet metal areas.

As a result of the superposition of the lines P and Q, i.e. as a result of the combined effect of the forced Tensile force and preheating, is in the skin sheet 1 caused a resulting residual tensile stress, which is shown in FIG. 6 by the line R. Consequently the entire sheet 1 does not contain any areas that are prone to deformation. In the from the framework 3 each limited rectangular fields 4a, therefore, there are almost no waviness or concave-convex def οrmations. It is therefore not an occasion given, in the completed roof cladding construction 4 deformations to remove.

It has been shown that by the method according to the invention in the roof lining construction one Vehicle deformations in the skin sheet can be almost completely avoided when using SPA-H (Japanese industrial standards) with a thickness of 1.2mm as a skin sheet, a forced tensile stress in the

Order of 25 kg / mm or more according to the stretching process described exerts induces or assists the skin panel in accordance with the described heating method to a temperature of 100 ⁰ C to 150 ⁰ C corresponding to the stretching and heating processes described a forced tension on the order of 15 kg / mm to the sheet metal and at the same time it is heated ^{to a temperature of about 50 ° C.}

Although the pure stretching process as well as the stretching and heating process with regard to a Stretching or stretching have been described in a single direction, the invention is based on a in one direction

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effective stretching is not limited. It is basically possible to apply a skin sheet in several directions stretch that do not need to be parallel to each other.

Furthermore, it is not necessary for the skin sheet to be a flat sheet of sheet metal. The invention is equally applicable to the production of cladding constructions with skin sheets that are not flat and on arched or otherwise shaped frameworks are attached. Such sheets of skin can have a single curvature ' or have a double curvature.

If it should be necessary in the practice of the invention, the skin sheet. 1 with a tension be overstretched that exceeds the elongation limit. This can remove tension that occurs during rolling of the sheet or during the side welding of the sheet metal elements. The overextension step can be performed prior to the three methods of manufacturing the panel construction described.

According to the invention, welding deformations and local deformations already existing in the sheet metal are thus eliminated removed by overstretching the skin sheet. In addition, by applying a uniform residual tensile stress as a result of elongation by a forced tensile force and preheating alone or in combination Deformations avoided. There are therefore virtually none in the entire panel or cladding construction Deformations. The usual operation for removing deformations can therefore be omitted.

For the above reasons, there is also the risk of material deterioration, material damage or other harmful effects on quality

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of the product decreased. Furthermore, the amount of work and energy required are lower. This affects advantageous on the manufacturing costs. The invention is therefore for the production of thin plate structures * ■ functions especially for vehicles, ships and structures suitable.

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Claims (21)

Claims 1.) Method for producing a panel structure from a skeletal framework and one on the A framework attached skin panel, characterized in that the skin panel has such a physical condition is imposed that it assumes a stretched state in its geometric surface that the skin panel is attached to the framework in this stretched condition and that thereafter the physical imposed on the skin panel Condition is released, with such residual tensile stress remaining in the skin panel that undesirable Deformations in the finished panel construction can be avoided. 2. The method according to claim 1,
characterized in that the physical condition is brought about by a tensile strain exerted within the geometrical surface of the skin panel which generates a forced tensile stress in the skin panel which does not exceed the elastic tensile elongation limit. 3. The method according to claim 1,
characterized in that the physical condition is established by heating the skin panel to a temperature above room temperature to produce thermal expansion within the geometrical surface of the skin panel, and in that the skin panel is affixed to the room temperature framework in the thermally expanded condition . 609 831/07 36 4. The method according to claim 1,
characterized in that the physical condition is brought about by a combination of a tensile elongation within the geometric surface of the skin panel in order to generate a forced tensile stress in the skin panel which does not exceed the elastic tensile elongation limit and by heating the skin panel to a temperature above room temperature in order to be within the geometrical To cause thermal expansion on the surface of the skin panel. 5. The method according to claim 2,
characterized in that a substantially planar skin sheet is used and the tensile elongation is caused in a single direction within the plane of the skin sheet. 6. The method according to claim 2,
characterized in that a substantially planar skin sheet is used and in that the tensile elongation is caused in non-parallel directions within the "plane of the skin sheet. 7. The method according to claim -3 »
characterized in that a substantially flat skin table is used, 8. The method according to claim 4,
characterized in that a substantially planar skin sheet is used and the tensile elongation is caused in a single direction within the plane of the skin sheet. 60 9 83 1/0736 9. The method according to claim 4,
characterized in that a substantially planar skin sheet is used and that the tensile stress is created in non-parallel directions within the plane of the skin sheet. 10. The method according to claim 2,
characterized in that a non-planar skin panel is used and that the tensile stress is produced in opposite directions, so that a tensile stress can be produced in a single direction at any point on the skin panel. 11. The method according to claim 2,
characterized in that a non-planar skin panel is used and in that the tensile stress is produced in opposite directions so that a tensile stress can be produced at any point on the skin panel in a number of mutually non-parallel directions. 12. The method according to claim 3,
characterized in that a non-planar skin table is used. 13. The method according to claim 4,
characterized in that a non-planar skin panel is used and in that the tension is generated in opposite directions so that a tension can be generated in a single direction at any point on the skin panel. 609831/0736 14. The method according to claim 4,
characterized in that a non-planar skin panel is used and in that the tension is exerted in opposite directions so that a tension can be produced in a number of non-parallel directions at any point on the skin panel. 1 5 . Method according to claim 1,
characterized in that the skin panel is made up of a number of panel elements which are laterally joined together. 16. The method according to any one of the preceding claims, characterized in that the skin panel prior to imposing the physical Condition is overstretched by subjecting it to a tensile stress that exceeds the tensile elongation limit. 17. The method according to any one of the preceding claims, characterized in η e t, that a thin sheet of metal is used as a skin board 18. Apparatus for exerting a tensile strain on a plate or board, in particular for use in the Method according to one of the preceding claims, characterized by a stationary, force-exerting part (8b) with a first Clamping head (10b), one attached to the clamping head first chuck (9b) for gripping one end of the plate or panel (1), a rod (8b,.), which at one end with a pin joint (13b) at a central pivot point of the remote from the chuck Clamping head is hinged, and a first anchorage (15b), which with a pin joint with the other 609831/0736 End of the rod is connected, and by a movable, force-exerting part (8a) with a second clamping head (10a), one attached to the second clamping head second chuck (9a) for engaging the other End of the plate or table, exerting a force Device (11, 11a), which at one end with a Pin joint (13a) at a central pivot point of the second, which is remote from the second clamping chuck The clamping head is articulated and at its other end is connected to a second anchorage (15a) which is shown in a distance from the first anchorage (15b) is arranged, and a drive device 12, 16) for driving the force-exerting device, the tensile forces measurable due to the drive to cause the tensile elongation generated. 19. The device according to claim 18, characterized in that that the force-exerting device comprises a hydraulic cylinder (11) and a piston with a piston rod (11a), and that the drive device is a hydraulic pressure system (12) which has a Hose (16) is in communication with the hydraulic cylinder. 20. Apparatus for stretching and heating a plate or table, in particular for use in the Method according to one of claims 1 to 17, characterized by a stationary, force-exerting part (8b) with a first clamping head (10b), a first clamping chuck (9b) attached to the clamping head for gripping the one end of the plate or panel (1), a rod (Sb ^), which at one end has a pin joint (13b) is connected to a central articulation point of the clamping head that is remote from the clamping chuck 609831/0736 is, and a first anchorage (15b), which is connected to the other end of the rod via a pin joint is, by a movable, force-exerting part (8a) with a second clamping head (10a), one on the second chuck (9a) attached to the second clamping head for gripping the other end of the plate or panel, a tension-exerting device (11, 11a), which at one end via a pin joint (13a) with a from the second chuck located central pivot point of the second clamping head is connected and at its other end is articulated to a second anchorage (15a) opposite the first anchorage (15b) is arranged spatially offset, and a drive device (12, 16) for driving the tension-exerting Device that, due to the drive, generates measurable tensile forces to cause overstretching, if necessary and the tensile elongation generated, and by heating means for preheating such parts of the plate or the board, where the tensile stress is not fully effective. 21. Apparatus according to claim 20, characterized in that the tension-exerting device is a hydraulic one Cylinder (11) and a piston with a piston rod (11a) and that the drive device a hydraulic pressure system (12) which is connected to the hydraulic cylinder via a line (16) stands. 609831/07 3 6